Skyline Graph

In this topic

Summary

The table and graph represent the horizontal and vertical angles going from the observer point to each of the vertices on the skyline.

Illustration

Usage

The azimuth and vertical angle from each observer point to each vertex in the skyline is evaluated, and can be exported to a stand-alone table by specifying the Output Angles Table. The following fields will be present in this table:

HORIZ_ANG—The horizontal angle.

ZENITH_ANG—The zenith angle.

If Additional Fields is selected:

FEATURE_ID—The skyline feature that obstructs the observer's view of the sky.

VERTEX_X—The X coordinate of the vertex.

VERTEX_Y—The Y coordinate of the vertex.

VERTEX_Z—The Z coordinate of the vertex.

DIST_2D—The horizontal distance from the observer to the
vertex.

DIST_3D—The slope distance from the observer to the vertex.

The arithmetic horizontal angle is equal to 90 minus the azimuth, and the zenith angle is 90 minus the vertical angle. (An arithmetic horizontal angle of 0 is due east, and 90 is due north; a zenith angle of 90 is horizontal, and 0 is straight up.)

The percentage of visible sky is always listed in the results. This value is equal to the area above the skyline, divided by the area above the base visible angle (one of the parameters, with a default of zero, meaning at the same elevation as the observer), and is calculated only within the azimuth range of the skyline.